World champions England will defend their title against New Zealand after a powerful second-half display saw them overcome France to reach the final.
A tight first half saw the sides reach the interval at 3-3 after Shannon Izar cancelled out Emily Scarratt’s penalty.
England upped their game in the second period and Scarratt edged them back in front with her second penalty.
Prop Sarah Bern drove over for a converted score to move England clear before Megan Jones’ last-gasp try.
They will now play New Zealand on Saturday at the Kingspan Stadium in Belfast, kick-off 19:45 BST, in a bid to retain the title they won against Canada in 2014.
Four-time champions the Black Ferns were far too good for the USA, running out 45-12 victors in the first semi-final.
Defence wins matches
England were under the cosh for long periods in the first half and the fact they had made over 50 tackles in the first 15 minutes showed just how hard France came at them.
However, the Red Roses’ white wall was unbreakable and when they finally lifted the siege, the psychological victory was probably as important as keeping the French scoreless.
In the second half England were much the better side and kept France pinned back for long periods, but even then it took two brilliant tackles to keep France out at a time when the champions only led by 10 points.
First Bern somehow held up Julie Annery as she stepped inside a yard from the line, and a minute later a desperate tackle from Jones saw the flanker just put a foot in touch as she dived over the line.
England up their game
Despite France’s pressure, England were level at the break and they looked like a side who never thought they could lose.
After the interval they turned up the power and, with front-foot ball to play with, the backs began to enjoy much more possession.
Even then the champions only led by three points entering the final quarter, before the relentless pressure they were applying finally told.
Bern was superb in both attack and defence and she popped up to dive over from close range.
As the game entered the final minutes England looked the fitter side and their suffocating defensive pressure saw Jones seize on a loose French pass to score with the clock deep in the red.
Champions do the basics well
The Red Roses were totally dominant in the line-out, stealing half a dozen French throws, which prevented Les Bleues from building momentum at crucial moments.
Goal-kicker Scarratt was her old self from the tee, landing two conversions and two penalties in another classy all-round performance.
One gliding break lifted the first-half siege and took England into French territory, before she popped up at the next phase to give winger Lydia Thompson the chance to attack with a crisp, first-time pass.
Katy Mclean’s kicking helped pin France back and although not every tackle was made, the total commitment in defence was key to subduing France – and is likely to be crucial once more against free-scoring New Zealand on Saturday.
Player of the match – Sarah Bern
Tight-head prop Bern has been in superb form all tournament, and the 20-year-old was once again a force of nature in Belfast.
The England scrum went into reverse on occasion against France, but at other times Bern and co shoved Les Bleues back at a rate of knots.
And around the park Bern was sensational, one moment smashing the French back in defence, the next powering forward with ball in hand.
Saturday’s World Cup final could be the first of three or four for the Bristol front-rower.
‘Our defence won that game’
England captain Sarah Hunter speaking to ITV: “It’s fantastic that we’ve come and done the job that we wanted to do. Our defence won that game. France came at us and they’ve given us the greatest test we’ve had so far in this tournament.
“We knew we had the mindset. Both defences stood up and the tackle count shows that, but we had a white wall and there was no way they were getting across our try line tonight.
“One try and France would have been back in the game but we pride ourselves on our defence and Megan Jones made a fantastic tackle [to deny Julie Annery].”